1. Field of the Invention
The invention relates to a method and system for locating a sound source in a water area by means of hydrophone listening, wherein at least three listening devices are provided each comprising a hydrophone and a radio transmitter with associated antenna and wherein there is further provided one radio master station to which signals indicative of sounds detected by the listening devices are transmitted and which station determines the geographical position of the sound source by correlating the said signals.
2. Description of the Related Art
A method and system for locating a sound source by means of hydrophone listening, which for example is described in U.S. Pat. No. 3,723,960, utilizes three hydrophone transducers connected by a radio link to a master station. The signals received by the master station are correlated in order to identify a common sound source. Then the times of arrival of a discrete sound emanated by the sound source are compared for determining the geographical position of the source. A problem with this system is that the coordinates of the hydrophone transducers must be known to some precision beforehand because, as the position of the sound source is determined with respect to the hydrophone, the precision with which the location of the source can be determined is dependent upon it.